Edit: I opened another tab in a separate Firefox container and didn’t get the pop-up. I believe I read this shit being account-based when the first reports of Youtube’s anti-adblock measures started making the rounds and it seems to be the case still
If anyone is looking for an alternative way to watch youtube videos without ads, FreeTube is a free and open source application that I would highly recommend. I prefer it over Invidious and Piped, and I haven’t had any issues with it so far !